Thermodynamic Model for Predicting Liquid Water−Hydrate Equilibrium of the Water−Hydrocarbon System

With the objective of estimating the solubility of a pure hydrocarbon hydrate former in pure water in equilibrium with gas hydrates, a simple thermodynamic model has been developed, based on the equality of water fugacity in the liquid water and hydrate phases. The solid solution theory of van der Waals−Platteeuw has been applied to calculate the fugacity of water in the hydrate phase. The Henry's law approach and the activity coefficient method have been used to calculate the fugacities of the hydrocarbon hydrate former and water in the liquid water phase, respectively. The results of this model are compared with some selected experimental data from the literature. Acceptable agreements between the model predictions and experimental data demonstrate the reliability of the model developed in this work. Finally, the possible errors sources in model predictions are discussed.

[1]  Cherl‐Ho Lee,et al.  Measurement and prediction of phase equilibria for water+CO2 in hydrate forming conditions , 2000 .

[2]  J. Lunine,et al.  Thermodynamics of clathrate hydrate at low and high pressures with application to the outer solar system , 1985 .

[3]  Peter Englezos,et al.  Effect of temperature and pressure on the solubility of carbon dioxide in water in the presence of gas hydrate , 2001 .

[4]  Vincent McKoy,et al.  Theory of Dissociation Pressures of Some Gas Hydrates , 1963 .

[5]  P. Englezos,et al.  Measurement of Dissolved Methane in Water in Equilibrium with Its Hydrate , 2002 .

[6]  Adam L. Ballard,et al.  The next generation of hydrate prediction , 2002 .

[7]  Y. P. Handa Effect of hydrostatic pressure and salinity on the stability of gas hydrates , 1990 .

[8]  W. Parrish,et al.  Experimental Thermodynamic Parameters for the Prediction of Natural Gas Hydrate Dissociation Conditions , 1980 .

[9]  Huen Lee,et al.  Measurement and prediction of phase equilibria for water + methane in hydrate forming conditions , 2001 .

[10]  C. S. Lee,et al.  Liquid Water−Hydrate Equilibrium Measurements and Unified Predictions of Hydrate-Containing Phase Equilibria for Methane, Ethane, Propane, and Their Mixtures , 2003 .

[11]  B. Buffett,et al.  Phase equilibrium of gas hydrate: Implications for the formation of hydrate in the deep sea floor , 1997 .

[12]  Phillip Servio,et al.  Prediction of methane and carbon dioxide solubility in water in the presence of hydrate , 2006 .